Comments

Honza's earlier change to the assert at the end of cdtor_comdat_group
was wrong; we really do need to make sure that we've created the '5'
group that we want. This is complicated by the change to alias creation
that automatically copies DECL_COMDAT_GROUP over, but since comdat
groups are copied from DECL_ASSEMBLER_NAME anyway, we can just look
there to find the names we want.
Tested x86_64-pc-linux-gnu, applying to trunk.